1. Field of the Invention
The present invention relates generally to a capacitor structure. More specifically, the present invention relates to a capacitor structure, which has a high capacitance per unit area.
2. Description of the Related Art
With the recent developments in the field of electronics, a large number of electronic products termed as ‘3C’ products such as computers, communication and consumer electronic products are being widely produced. These electronic products require a variety of semiconductor components, which have different functions. Therefore, an application specific integrated circuit (ASIC) has been developed for manufacturing and integrating semiconductor components in accordance with their different requirements. For example, a mixed mode circuit (MMC) is a type of ASIC wherein a capacitor and a complementary metal oxide semiconductor (CMOS) are integrated.
In general, in the mixed mode circuit described above, a capacitor is a basic and an important electronic component. Especially, in analog basic building block circuits such as sample and hold circuits, analog to digital (A/D) converters, digital to analog (D/A) converters or switched capacitor filters, a capacitor is an important and indispensable component.
In the recent times, in order to minimize the size of electronic devices and make them compact, the size of their components also needs to be minimized. However, in general a capacitor occupies a large area of the layout of the chip comprising an electronic device. Therefore, in a high performance mixed mode circuit, the mixed mode circuit (MMC) capacitor structure is developed using a material, which has a high dielectric constant in order to increase its capacitance per unit area. However, the MMC capacitor structure has the disadvantages of a high manufacturing cost, a long process time and a complex manufacturing process. Therefore, there is a requirement for a capacitor, which has a low manufacturing cost and a high capacitance per unit area.